German patent specification DE 103 16 632 B4, for instance, discloses a screw bolt having a so-called load-indicator disk, also referred to as a “direct tension indicator” (DTI). Such an indicator has sensors for checking the tension set on the screw bolt, whereby the sensors consist of capsules that are filled with a dye. At a predefined axial load, the dye comes out of the indicator and/or becomes visible at the edge of the indicator. Therefore, the sensors can confirm that the target tension has been reached without the need to detect the installation torque.